The
Baal Shem Tov, or Besht — the founder of Chasidism —
met the soul of the Messiah during an ascent to heaven.
The Besht asked him, "When will the Master come?"
The Messiah answered, "When your wellsprings break forth to the outside!"
(from a letter
written by the Besht to his brother-in-law about one of his soul ascents)

Nigun Ha'Ari / Shir Hama'alot (Dovid Din)

I learned this nigun from Shaul Magid as a composition by R. Dovid Din to Shir Hama'alot. (Dovid Din's remarkable story bears telling and perhaps someday I'll add it to neohasid.) Yoram Getzler z"l, who sent neohasid an instrumental rendition from his album Niggun, Nishama, Haftaah in 2006, told me that people are now connecting this nigun to the Ari (Isaac Luria). Read Yoram's words, learn more about him, and listen to some of his other musical pieces here. I asked Shaul some more questions about this nigun's provenance and this was his answer:

I got Yoram's beautiful rendition. I also sent to it Zalman who loved it as well. Zalman and I talked about its origins. My recollection is that
Dovid claimed to have written it in the House of Love and Prayer. I am
not sure how it became known as the Ari's niggun. Others have claimed
that, in fact, it originated with Yankele Shamash from the House of Love
and Prayer (then of Modiim). In any case, Dovid really owned it and made it
what it was. I only heard Dovid sing it to Shir Ha-Maalot. I have heard
that Yankele used it for Shalom Aleikhem but I can't verify that. [Note: Yoram's "Ari" version was also taught to him as a tune for Shalom Aleikhem.]

Whether it's from Dovid Din or Yamkele Shamash, it's a beautiful and soulful melody and it's easy to see why people imagined it coming form the Ari.